1. Field of the Invention
The present invention relates to web handling and storage apparatus as, for example, photographic film used in a reconnaissance airplane.
2. Description of the Prior Art
The storage and handling of long webs of material such as film or tape is often a difficult problem. For example, when it is desired to view a film at various speeds, including reverse and still, and the film is stored in a storage mechanism that may be receiving tape at the same time, a number of problems are encountered. An example of a system that has been used widely in the prior art is referred to as a "slack box" in which the film is stored loosely in a container and withdrawn therefrom for viewing at any desired rate. The difficulty with such a system is that the film can become tangled, particularly in situations where violent movement may be involved such as when the system is used in aircraft. A system which solves this problem is found in a co-pending application Ser. No. 935,905 of T. Khoen Liem filed Nov. 28, 1986 and assigned to the assignee of the present invention and now U.S. Pat. No. 4,772,952 issued Sept. 20, 1988. In this disclosure, a plurality of rollers each independently rotatable about their own axis are mounted on a member which rotates about a central axis. The film is wound around the rollers to provide an interim storage. When desired, the inner layer of film is removed from the interior of the coil and passed by a viewing mechanism mounted on the rotatable member and taken up in a second storage reel, also mounted on the rotatable member. The second rotatable member can withdraw the film at any speed desired or stop entirely or, even reverse, and does so without becoming tangled. There are, however, several difficulties encountered in the apparatus described in the above-mentioned co-pending application. The electrical signals to and from the optical viewing system have to be brought out through slip rings which create noise and have other disadvantages and the rotating member must remain dynamically balanced and be very large in order to carry both the take-up reel and th film viewing system.